Important Announcement
PubHTML5 Scheduled Server Maintenance on (GMT) Sunday, June 26th, 2:00 am - 8:00 am.
PubHTML5 site will be inoperative during the times indicated!

Home Explore Service Manual - MCM1062R

Service Manual - MCM1062R

Published by Scotsman®LATAM, 2016-07-23 13:36:19

Description: Service Manual - MCM1062R


Read the Text Version

MCM1062RINTRODUCTIONThis manual is intended as a reference for theinstallation and service of a Scotsman ice makermodel MCM1062.This model is a remote condenser cuber, 30\" wideand may be connected to a Mac 6 or a Scotsmanremote condenser. This ice machine uses R-22. TABLE OF CONTENTS PageSpecifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Environmental Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3For the Installer Machine & Bin Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 For the Plumber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Remote Condenser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Coupling Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9For the Electrician . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Final Check List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Initial Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Component Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Service Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Service Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Removal and Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Parts lists and wiring diagrams are in the center of this manual, printed on yellow paper.October 1993 Page 1

MCM1062RSPECIFICATIONSAlways refer to the nameplate, located on the backof the cabinet, for the: •model number, •serial number, •basic electrical requirements, •minimum circuit ampacity, •maximum fuse size, •and refrigerant charge.A serial number plate with themodel number, serial number and refrigerantcharge is located behind the front panel, near thecontrol box.The unit comes from the factory with the correctrefrigerant charge contained in the receiver. Therefrigerant charge information is for recharging,should that be necessary.All utility connections and refrigerant lineconnections are made at the back of the ice maker.Before beginning installation, be sure that all of thecomponents necessary for complete assembly ofthe ice system are available, and are the correctcomponents with regard to model, voltage, andfinish.Installer: After installation, take this manualwith you, do NOT leave it with the machine. October 1993 Page 2

MCM1062RFOR THE INSTALLER: Environmental LimitationsInstallation Limitations Water LimitationsThe ice making portion of this ice system is An ice machine is a food manufacturing plant; itdesigned to be installed indoors, in a controlled takes a raw material, water, and turns it into a foodenvironment. product, ice. The purity of the water is very important in obtaining pure ice and in maximizingAir Temp Minimum Maximum product life. These general recommendationsWater Temp 500F. 1000F. should help keep the ice maker clean: 400F. 1000F. 1. Filter the water used to produce ice. Water filtersWater Pressure 20 PSI 80 PSI vary greatly in ability and function. Install one that filters out suspended solids to a dimension of 5Voltage 197 253 microns or smaller. The finer the filter the better, but finer filters will clog sooner than course ones. ItOperating the ice machine outside of the above may be necessary to add a course filter ahead oflimitations, or outdoors, is potentially damaging to the fine filter to prolong filter life.the machine; also it is misuse of the machine,which may void the warranty. 2. Check with a water treatment specialist for a water test, and recommendations regarding filtersScotsman Ice Systems are designed and and treatment.manufactured with the highest regard for safetyand performance. They meet or exceed the Service Limitationsstandards of UL, NSF, and CSA. Some space on the sides, the back and the topScotsman assumes no liability or responsibility of should be allowed for service and utilityany kind for products manufactured by Scotsman connections.that have been altered in any way, including theuse of any part and/or other components notspecifically approved by Scotsman.Scotsman reserves the right to make designchanges and/or improvements at any time.Specifications and design are subject to changewithout notice. NAMEPLATE, LOCATED ON BACK PANEL. A SERIAL NUMBER PLATE IS LOCATED BEHIND THE FRONT PANEL, NEAR THE CONTROL BOX. October 1993 Page 3

MCM1062RFOR THE INSTALLER: Machine & Bin AssemblyOverview: Ice Maker:This ice system is comprised of 4 major 1. Arrange for proper electric, water and drain.assemblies: See instructions for the plumber and for the1. The ice storage bin. electrician.2. The ice maker itself. 2. Position the ice storage bin in the selected location which should have a minimum room3. The interconnecting refrigerant lines. temperature of 50-degrees F. and maximum room temperature of 100 degrees F.4. The remote condenser. 3. Inspect the bin top mounting gasket whichAdditionally, there will be interconnecting wires should be flat, with no wrinkles, to provide a goodbetween the ice maker and the condenser. The water seal when the cuber is installed on top of theScotsman remote condenser is powered from the maker. The condenser must be located abovethe ice maker, usually on the roof. 4. Install the modular cuber on top of the bin using care to be sure a good seal is made between theStorage Bin: two cabinets, use of a mechanical lift is recommended. Align the holes in the bottom back1. Measure the location of the ice machine floor of the cabinet to mate with the two mounting strapsdrain relative to the installed location of the bin. on the top rear of the bin.Route all drain lines so that when the machine isinstalled in its normal position, the drain tubes 5. Use bolts and straps found in the hardwareterminate just above the floor drain. package to secure the ice machine to the ice storage bin. Attach the bin bumpers to the bin with2. Using corner posts from the bin’s carton as a the bolt holding the mounting strap to the bin.cushion, lay the bin on its back. When alignment and leveling are completed,3. Install the casters into the leg sockets. tighten the bolts to secure the mounting straps.4. Move bin back to an upright position.5. Check that the back set of casters are in in lineto allow the bin to be rolled back and forth.7. Hang the scoop holder and scoop from the frontedge of the bin (inside the bin).8. Install the bin bumpers at the back of the bin.9. Remove all material that is packed inside the bin. MOUNTINGSTRAPS AND BOLTS BIN BUMPER 5\" MEASURE THIS FLOOR DRAINOctober 1993 DISTANCE Page 4

MCM1062RFOR THE PLUMBERWater SupplyThe recommended water supply line is a 3/8-inchO.D. tubing with a minimum operating pressure of20 PSIG and a maximum of 80 PSIG.Connect to cold water supply line with standardplumbing fittings, with shut off valve installed in anaccessible place between the water supply andthe cuber. ln some cases a plumber will berequired.Drain Connections:Drain tubing and fittings are supplied with the icebin. All drains are gravity type and must have aminimum of 1/4-inch fall per foot on horizontalruns. The drains to be installed must conform withthe local plumbing code.Install a vertical open vent on the drain line(s) highpoint to ensure good draining. The ideal drainreceptacle is a trapped and vented floor drain.October 1993 Page 5

MCM1062R SCOTSMAN REMOTE CONDENSERFOR THE INSTALLER: Remote Condenser PRE-CHARGEDScotsman Condenser: REFRIGERANTLocate the condenser as near as possible to the LINE SETinterior location of the ice maker. FLEXIBLELocation of the condenser is limited by the TUBING ENDspecific length of pre-charged refrigerant tubingsupplied for the application. The pre-chargedtubing connects the icemaker to the remotecondenser. The condenser must be above the icemaker.Select the best available location, protecting thecondenser from extremes of dirt, dust, and sun.Meet all applicable building codes.Roof Attachment:Install and attach the remote condenser unit tothe roof of the building, using the methods andpractices of construction that conform to the localbuilding codes, including having a roofingcontractor secure the condenser to the roof.October 1993 Page 6

MCM1062RFOR THE INSTALLER: Remote Condenser (Scotsman)Pre-charged Line Routing/////////////////////////////CAUTION///////////////////////////////Do not connect pre-charged tubing until all routing REMOTEand forming of the tubing is complete. See the CONDENSERcoupling instructions for connecting instructions. (SCOTSMAN)//////////////////////////////////////////////////////////////////////////// SPIRAL EXCESS1. Each set of precharged refrigerant lines consists TUBINGof a 3/8 inch diameter liquid line, and a 1/2 inchdiameter discharge line. Both ends of each line HEREhave quick connect couplings, one end has flexibletubing: that end goes to the icemaker.Note: The openings in the building ceiling or wall,listed in the next step, are the minimum sizesrecommended for passing the refrigerant linesthrough.2. Have the roofing contractor cut a minimum holefor the refrigerant lines of 1.75\". Check localcodes, a separate hole may be required for theelectrical power to the condenser./////////////////////////////CAUTION////////////////////////////////DO NOT KINK OR CRIMP REFRIGERANT LOOP OFTUBING WHEN INSTALLING IT. FLEXIBLE TUBING////////////////////////////////////////////////////////////////////////////3. Route the refrigerant lines through the roofopening.Follow straight line routing whenever possible.Any excess tubing MUST be retained within thebuilding.4. Spiral any excess length of pre charged tubinginside the building. Use a horizontal spiral (asillustrated) to avoid any traps in the lines.5. Have the roofing contractor seal the holes in theroof per local codes.6. The flexible line end must be installed behindthe icemaker, it is to be looped down from the icemachine connection area then back up to the wallbehind the ice machine. This allows the icemachine to be pulled out for service.October 1993 Page 7

MCM1062RFOR THE INSTALLER: Remote Condenser (Mac 6)Precharged Line Routing////////////////////////CAUTION///////////////////////////////Do not connect precharged tubing until all MAC6 REMOTE UNITrouting and forming of the tubing is complete.See the coupling instructions for connecting ELECTRICALinstructions. CONNECTION/////////////////////////////////////////////////////////////////////// LIQUID LINE1. Each set of precharged refrigerant linesconsists of a 3/8 inch diameter liquid line, anda 1/2 inch diameter discharge line. Both endsof each line have quick connect couplings,one end has flexible tubing: that end goes tothe icemaker.Note: The openings in the building ceiling orwall, listed in the next step, are the minimumsizes recommended for passing therefrigerant lines through.2. Have the roofing contractor cut a minimumhole for the refrigerant lines of 1.75\". Checklocal codes, a separate hole may be requiredfor the electrical power to the condenser.///////////////////////CAUTION////////////////////////////////DO NOT KINK OR CRIMP REFRIGERANT FLEXIBLETUBING WHEN INSTALLING IT. END///////////////////////////////////////////////////////////////////////3. Route the refrigerant lines through the roofopening.Follow straight line routing whenever possible.Any excess tubing MUST be retained withinthe building.4. Spiral any excess length of pre chargedtubing inside the building. Use a horizontalspiral (as illustrated) to avoid any traps in thelines.5. Have the roofing contractor seal the holesin the roof per local codes.6. The flexible line end must be installedbehind the icemaker, it is to be looped downfrom the ice machine connection area thenback up to the wall behind the ice machine.This allows the ice machine to be pulled outfor service. October 1993 Page 8

MCM1062RFOR THE INSTALLER: Coupling Instructions/////////////////////////////CAUTION///////////////////////////// 4. Using a marker or pen, mark a line lengthwise from the coupling union nut to the bulkhead. ThenThe couplings on the sets of precharged lines are tighten the coupling and additional 1/4 turn. As theself sealing when installed properly. Carefully nut turns, the line will show when 1/4 turn is made.follow the instructions: 5. After all connections are made, and after the////////////////////////////////////////////////////////////////////////// king valve has been opened, check the couplings for leaks.1. Remove the protector caps and plugs. Wipe theseats and threaded surfaces with a clean cloth tobe certain that no foreign matter remains on them.2. Lubricate the inside of the couplings, especiallythe O-Rings with refrigerant oil. • The 3/8 inch liquid line (schrader valve end) goes to the remote condenser fitting marked “liquid line”. • The other end of the liquid line goes to the icemaker fitting marked “liquid line.” • The 1/2 inch discharge line (schrader valve end) goes to the remote condenser fitting marked “discharge line”. • The other end of the discharge line goes to the icemaker fitting marked “discharge line”.3. Begin tightening the couplings together byhand, then using two wrenches (it is important thatONLY the nut on the precharged lines be turned,the other parts of the couplings must NOT beallowed to turn or the process will tear out thediaphragms and they will be loose in therefrigeration system) tighten the coupling until itbottoms out or a definite increase in resistance isfelt. ONLY TURN NUT ON TUBING KIT, HOLDTUBING STATIONARY USE TWO WRENCHES October 1993 Page 9

MCM1062RFOR THE ELECTRICIAN: Electrical ConnectionsSee the NAMEPLATE for current requirements to /////////////////////////////CAUTION///////////////////////////////determine wire size to be used for electricalhookup. The cuber requires a solid chassis to Do not switch the ice maker on at this time, makechassis earth ground wire. See Wiring Diagram. certain the master and compressor switches are OFF when power is connected to the icemaker.Be certain the cuber is connected to its own Power must be connected to the ice maker longelectrical circuit and individually fused. Voltage enough in advance of start up to allow thevariation should not exceed ten percent of the crankcase heater to warm the compressor, usuallynameplate rating, even under starting conditions. about 12 hours.Low voltages can cause erratic operation and maybe responsible for serious damage to the //////////////////////////////////////////////////////////////////////////////icemaker. Scotsman Condenser:Electrical connections are made at the rear of theicemaker, inside the junction box. Separate electrical connections are made from the ice maker to the condenser, as there is line power interconnecting the icemaker to the condenser. All external wiring should conform to the national, state and local electrical code requirements. Usually an electrical permit and services of a licensed electrician will be required. REMOTE CONDENSER ELECTRICAL CONNECTION (SCOTSMAN CONDENSER) POWER SUPPLY TO REMOTE SCOTSMAN CONDENSER POWER SUPPLY TO ICE MAKERTERMINAL STRIPS October 1993 Page 10

FOR THE INSTALLER: Final Check List MCM1062R1. Is the ice maker cabinet in a room where THE COMPLETEDambient temperatures are within the minimum and INSTALLATION SHOULDmaximum temperatures specified? GENERALLY APPEAR AS2. Is there clearance at both sides of the cabinet ILLUSTRATED HEREand at the back and top for service and utilityconnections? EXCESS TUBING LOOPED HERE3. Has water supply pressure been checked to FLEXIBLE TUBINGinsure a minimum of 20 PSIG and a maximum of ELECTRICAL POWER80 PSIG operating pressure? TO CONDENSER4. Is the cabinet level? ELECTRICAL POWER5. Check that any shipping material has been CORDremoved from inside the cabinet. DRAINS6. Have all electrical and piping connections beenmade?7. Are the Master and Compressor switches onOFF?8. Has power been REMOTEconnected to the ice CONDENSERmaker? (MAC 6)9. Is the water supply lineshut off valve installed?10. Check all refrigerantlines and conduit lines, toguard against vibration orrubbing and possiblefailure.11. Have the bin andcabinet been wiped cleanand sanitized?12. Has the Field Quality POTABLEAudit form been properly WATERfilled out? Check for INLETcorrect model and serialnumbers from Serialnameplate, then mail thecompleted form to theSCOTSMAN factory.13. Has the owner beengiven the name andtelephone number of theauthorized SCOTSMANService Agency servinghim? October 1993 Page 11

MCM1062RINITIAL START UPRemote Condenser: EVAPORATOR1. Check that all connections have been made. COVERIce Maker:1. Remove front panel by pulling out to unsnap.2. Remove two screws and the control box cover.3. Remove the evaporator cover.4. Remove the left side service panel.5. Check that the ON/WASH/OFF rocker switch ON/WASH/OFFand the Compressor ON-OFF toggle switch are in SWITCHthe OFF position, on the control box.6. Locate and open the king (service) valve on thereceiver. Check that the crankcase heater has “KING”been on long enough to warm the compressor VALVEdome (about 12 hours).7. OPEN the water supply line shut off valve. 9. Observe water fill cycle: The water inlet solenoid valve OPENS,and water flows from the8. Inside the control box is the shaft of the timer valve to the reservoir. The reservoir fills andand the switch assembly. Rotate the shaft of the excess water drains out the machine drain. At thetimer and switch assembly clockwise to where the end of the harvest cycle, the water inlet solenoidactuator arm on the microswitch drops off outer valve will close and the water fill cycle is into cam slot. See Timer Cam Positions. If the reservoir is not full, advance the shaft of the timer clockwise into a new harvest cycle; this8. Move the ON/WASH/OFF rocker switch to the opens the water valve again. The water pump willON position. be pumping water over the evaporators. TIMER CAM POSITIONS 10. Check that the water cascades down over each cube mold and into the reservoir.ACTUATOR MICROSWITCH 11. When the reservoir is full, move theCAM & compressor ON-OFF toggle switch, to the ONSHAFT position. HARVEST 12. Check operation of the freezing cycle: Ice PORTION begins to form from the top of the evaporator down. Freezing time will range between 13 and 15FREEZE minutes. Longer time for temperatures above 70PORTION degrees F. and shorter time required when temperatures are below 70-degrees F. Average complete cycle time is about 16 minutes. 13. Check CUBE SIZE The dimensions of the cubes are fixed by the size and shape of the molds on the evaporator plate, except that the thickness of the cube MAY need to be adjusted at start up. There is only one size of cube that is correct; adjusting the cube size control to that size of cube will allow the ice maker to produce ice at its most efficient size. The correct size cubes will appear similar to the illustration for “Correct Size Cube”. October 1993 Page 12

INITIAL START UP MCM1062RAdjust for the correct size if needed: Locate CUBES (ACTUAL SIZE)cube size control knob in the front of the controlbox. Rotate this knob one eighth of a turn TOO THICK •Counter clockwise to produce SMALLER sized 1 1⁄4\" ice cubes or CORRECT •Clockwise to produce LARGER ice cubes SIZE 1 1⁄4\" CUBEObserve size of the ice cubes in the next ice cubeharvest and adjust again if needed, until the Note:Optimum perfromance will be achieved whencorrect ice cube is achieved. the ice machine is adjusted to porduce this size and14. Check Harvest Time. shape of cube. The typical batch weight at this setting is between 8.25 and 9 pounds.The harvest time is determined by the gap in thetimer cam. That gap may be adjusted if needed. TOOThe correct harvest time is when there are about THIN15 seconds of time left in the harvest cycle afterthe last cube has fallen from the evaporators. See 3. To test, wait until the ice machine is near thethe next page for detailed adjustment instructions. end of a “harvest” cycle, if there is ice in the binDo not adjust harvest time TOO SHORT or the higher than the position the ice level control is setmachine will not harvest all the ice. for, the ice machine will turn OFF at the end of the harvest cycle. If no ice in the bin, test again as15. Check ICE BIN LEVEL CONTROL described under, “To Test The Ice Level Setting”. 16. Replace all panels & covers.The amount of ice maintained in the bin is 17. Fill out and mail in the Customer Evaluationadjustable. The normal setting is “full”. If the and Warranty Registration form. Inform the useroperator desires, the level of ice in the bin may be how to call for service and the maintinanceadjusted lower to shut off the machine when the requirements of the machine.bin is only partially full. The ice bin level control isdesigned for the MDB550 ice storage bin, use ofother bins may result in ice levels that are more orless than the settings on the control indicate.To Test The Ice Level Setting:1. Open the bin door and locate on the bottom ofthe ice machine, the ice level sensor. It’s in asocket about 2\" in diameter and located left of theevaporator plates.2. When the machine is running, wait untIl near theend of a “harvest” cycle.3. Hold a flat object about the size of this servicemanual over the ice level sensor socket.4. The ice machine should turn off at the end of theharvest cycle.5. Slowly lower the flat object straight down.6. The ice machine will start again at the pointwhere it will maintain the ice level.Adjust Bin Ice Level1. Locate ice level control switch.2. Move switch to the desired position.October 1993 Page 13

MCM1062RADJUSTMENTS TIMER CAM POSITIONS Adjustment Of The Timer & Switch AssemblyACTUATOR MICROSWITCH One complete revolution of the cam on the timer represents eight minutes. If left as factory set, fourCAM & and one-half minutes comprise the freezing cycleSHAFT portion during cam rotation, and the final three and one-half minutes is the defrost/harvest cycle. HARVEST Rotating the shaft of the timer cam clockwise will PORTION put the ice machine in the freeze or harvest cycle.FREEZE ////////////////////////////// WARNING ///////////////////////////////PORTION Disconnect electrical power supply to icemaker whenever adjustment procedures are performed. TIMER ADJUSTMENTMICROSWITCH /////////////////////////////////////////////////////////////////////////////// SHAFT OF To adjust the timer & switch assembly: CAM 1. Remove front panel. 2. Remove control box cover. A. To start the HARVEST CYCLE: Slowly rotate the shaft of the timer and switch assembly clockwise until the actuator arm on the microswitch begins the harvest cycle. An audible click can be heard, but in a noisy area, look at the cam and switch to observe the event B. To start the FREEZING CYCLE: Slowly rotate the shaft of the timer and switch assembly clockwise, until the actuator arm on the microswitch starts the freezing cycle. C. To adjust the length of the harvest cycle: 1. Loosen the adjustment screw on the cam, and rotate the shaft of the cam to move the top part of the assembly. More of a gap between the high and low portions will yield more harvest time. 2. Tighten the set screw. 3. Replace the control box cover and front panel. lt is important that the length of the harvest cycle allow enough time for all the ice cubes to fall from the evaporator. Too short of a time will cause the evaporator to freeze up and stop ejecting ice into the bin. Too much time wastes icemaking capacity, energy and water. Adjustment of the harvest cycle may require an adjustment of the cube size control.SET SCREW October 1993 Page 14

COMPONENT DESCRIPTION MCM1062RCompressor Contactor Hot Gas Solenoid ValveThe compressor contactor carries the compressor The hot gas solenoid valve opens only during theline current. The contactor is wired so any control harvest cycle. When it opens, it diverts the hotin the pilot circuit, such as the bin control, and high discharge gases so that they flow directly into thepressure controls, etc., will cause the contactor evaporator plates, by-passing the condenser andholding coil to be de energized, when the control thermostatic expansion valve. The hot gases warmcontact OPENS, thereby breaking the circuit to the the evaporators, releasing the ice cubes from thecompressor. ice cube molds. The hot gas solenoid valve is installed in a branch of the discharge line from theCube Size Control compressor, and when the timer switches the ice machine into the harvest cycle, the energizedThis reverse acting (closes on temperature fall) solenoid coil lifts the valve stem within the valvethermostat determines how long the freezing cycle body, allowing the hot discharge gas to be divertedwill be. The cube size control closes its contacts to the evaporators.when the evaporator cools to the set temperature,starting the timer. A variation in heat load (either High Temperature Cut Outambient air or incoming water temperature) willaffect the efficiency of the refrigeration system, and This temperature sensor is located next to the hotthat will vary the length of time it takes the gas valve, on the outlet side.evaporators to cool to the temperature at which thecube size control is set to close, which, in turn, will During normal operation, it does not affect the iceaffect the overall cycle time. See CUBE SIZE machine, but it will shut the machine off if the hotADJUSTMENT BEFORE attempting to adjust the gas line overheats. It is an automatic reset.control.RelayThe multi-function, three pole, double throw, relayplugs into a socket on the printed circuit board inthe control box. The relay functions in part toby-pass the bin control during the harvest andfreeze cycles, preventing the icemaker fromshutting off in the middle of a cycle. The bypassaction allows only complete freeze and harvestcycles; the only time that the ice maker can shutoff on bin control is as the end of the harvest cycle.Timer - Timer & Switch AssemblyThe timer begins to turn when activated by thecube size control. The outer surface, or largediameter lobe of the timer cam, determines thelength of time for finish freezing of the ice cubes,while the inner surface, or small diameter lobe,determines length of the harvest cycle. Thesingle-pole, double throw microswitch on the timercontrols the power to the plug in relay coil, makingit either the freezing or harvest cycle. Themicroswitch is actuated by a cam assemblydirectly connected to the timer motor. The timercam can be adjusted to vary the defrost time, asrequired. One complete rotation of the cam willtake eight minutes. Harvest is preset at 2 and aquarter minutes.October 1993 Page 15

MCM1062R ON/OFF/WASH SWITCHCOMPONENT DESCRIPTIONIce Level ControlThis electronic control uses sound waves tomeasure the distance between the bottom of theice machine and the top of the ice in the bin. It isdesigned to control the machines ice production tomaintain that distance.The control is adjustable so that the ice machinewill maintain a certain height of ice. It will not fillany closer to the ice machine than 8\", and will notwork if the distance to the bottom of the bin isgreater than 8 feet.Because it uses sound waves, a slight “ticking”sound can be heard coming from the bottom of themachine.ICE LEVELSELECTOR SWITCH SOUND THE USER CAN WAVES SELECT THE AMOUNT OF ICE TO BE MAINTAINED IN THE BIN. FULL 3⁄4 1⁄2 1⁄4 October 1993 Page 16

COMPONENT DESCRIPTION MCM1062RElectric Water Inlet Valve Reservoir The reservoir, located below the evaporators,The water inlet solenoid valve fills the reservoir stores the inlet water charge, and collects theassembly with water. Excess water overflows out water that flows over the evaporator plates.the overflow standpipe located at the back of the Strainerreservoir. This action fills and rinses the reservoir A water strainer is located in the potable inlet waterduring each harvest cycle. The flow rate is .75 line before the water inlet solenoid valve. Cleang.p.m. the water strainer as needed. High Pressure Safety ControlWater Distribution System This is a manual reset control that shuts down the icemaker, should the discharge pressure everThe water distribution system evenly supplies reach 400 PSIG.water to all cells of the evaporator plates. Thewater pump pumps water from the reservoir up thevertical tygon tube to the tee. From there water ischanneled through the water manifold to the waterdistributors, above each evaporator plate, andfrom six holes within each distributor, water flowsto the cells of each side of the evaporator plates.Gravity flow returns the unfrozen excess portion ofwater to the reservoir for recirculation. WATER DISTRIBUTION SYSTEM EVAPORATOR WATER PUMPSTRAINER RESERVOIR HIGH PRESSURE CUT OUT ELECTRIC WATER VALVE October 1993 Page 17

MCM1062RSERVICE SPECIFICATIONSWhen servicing a machine, it’s helpful to comparethat unit’s operating characteristics to those of anew, clean, normally operating machine. Whatfollows is that type of information: COMPONENTSTimer: Makes one complete revolution in 8 minutes. The harvest time is factory preset at 2 1⁄4 minutes.The harvest time is adjustable as required.Inlet Water Valve: Opens and admits 3⁄4 gallon per minute during the harvest cycle.Cube Size Control: Reverse acting temperature control, contacts close between 240F. and 00F. Typicallyadjusted to close at 130F.Pump Down Control: Contacts open at 20 P.S.I.G. and close at 35 P.S.I.G.High Pressure Safety Switch: Contacts open at 400 P.S.I.G.Bin or Ice Level ControlMaximum Full Height 8\" from the base of the ice machine.Partial Setting 21\" - 22\" from the base of the ice machine.Maximum Storage Bin Interior Height 8’ from the base of the ice machine. OPERATING CHARACTERISTICSThe values listed below are representative of 275-210 P.S.I.G.values seen at a wide range of air and water 24-20 P.S.I.G.temperatures and are for a normal cube size. 15-17 minutesTemperatures are Condenser/ Ambient Air/ WaterFREEZE CYCLEAverage Discharge Pressure at Average Temp.Suction pressure at the end of the freeze cycleFreeze TimeHARVEST CYCLEAverage Discharge Pressure 175 P.S.I.G.Average Suction Pressure Lo Temp (0/70/55) 75-80 P.S.I.G. Average Temp (90/90/70) 80-90 P.S.I.G. High Temp (110/90/80) 90-100 P.S.I.G.Harvest time is assumed to be 2.25 minutes. This can be adjusted to suit local conditions.This unit uses R-22. The system charge is 256 ounces. If the nameplate lists a different quantity ofrefrigerant, go by the nameplate. October 1993 Page 18

MCM1062RCLEANING///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////A Scotsman Ice System represents a sizable investment of time and money in any company’s business. Inorder to receive the best return for that investment, it MUST receive periodic maintenance.Maintenance and Cleaning should be scheduled at a minimum of twice per year.//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////CLEANING: ICEMAKER 9. Switch the machine to “wash” and continue to///////////////////////////////WARNING///////////////////////////// add fresh water to flush residual cleaner from theElectrical power needs to be on when doing in system. Switch the Wash/Off/Ice switch cleaning.///////////////////////////////////////////////////////////////////////////// 10. Sanitize the ice maker and bin, see “Sanitize1. Remove front panel. Water System”.2. Switch the Wash/Off/Ice switch to OFF.3. Remove the front liner. 11. Replace the front liner.4. Remove and discard all ice from the storage bin. 12. Switch the Wash/Off/Ice switch back on. 13. Replace the front panel 14. Check the next batch of cubes to make sure all of the acid taste is gone.5. Locate the reservoir drain cap, remove the cap /////////////////////////////////CAUTION//////////////////////////////and drain the reservoir. Replace the drain cap. Ifthe reservoir doesn’t drain completely, disconnect DO NOT use ice produced from the cleaningthe pump hose attached to the water distributors solution. Be sure none remains in the bin.and place the end of the hose in a bucket. Switchthe Wash/Off/Ice switch to Wash, and allow the ////////////////////////////////////////////////////////////////////////////////pump to discharge the rest of the water. Reattachthe hose to the water distributors. 15. Remove and discard all ice from the storage bin, pour hot water into the storage bin to melt the6. Mix 8 ounces of Scotsman Ice Machine Cleaner cubes and also clean out the bin drain. Scotsman Ice 16. The unit is now ready for continued automatic Machine Cleaner operation. contains acids. These compounds Strainer: may cause burns. A water strainer is located in the water line before If swallowed, DO NOT the inlet water solenoid valve. It is designed to induce vomiting. Give catch large particles that may be in the water. To large amounts of water clean: or milk. Call Physician 1. Shut off immediately. In case of water supply. external contact, flush 2. Unscrew with water. screen from KEEP OUT OF THE strainer. REACH OF CHILDREN. 3. Brush particles fromwith 1 gallon of warm (950F. - 1150F.) water and screenpour into the reservoir until full. 4. Replace screen in7. Switch the Wash/Off/Ice switch to “wash”. Let strainer.the unit operate for 30 minutes, then switch the 5. Turn waterunit off. supply back on.8. Drain the reservoir again (repeat step 5). SCREEN October 1993 Page 19

MCM1062R SCOTSMAN REMOTE CONDENSERCLEANING 1. Disconnect electrical power at the icemaker.SANITIZE WATER SYSTEM ///////////////////////////////WARNING///////////////////////////1. Remove and discard all ice from the bin. Disconnect electrical power before beginning.2. Remove front panel. ////////////////////////////////////////////////////////////////////////////3. Drain the reservoir 2. Wipe off any surface dust from the intake side of the condenser.4. Prepare 2 gallons of an approved sanitizersolution in accordance with the instructions on the 3. Vacuum the coil, or clean with coil cleaner.package. 4. The coil is clean when light can be seen through5. Pour 1 gallon of the sanitizer into the ice maker the fins.reservoir. 5. Reconnect electrical power.6. Move the main switch to “Wash”, and allow thesolution to circulate for a MINIMUM of 5 minutes. SANITIZE ICE STORAGE BIN7. Move the main switch to “Off”. This procedure is to be done monthly8. Pull out the drain plug and drain the reservoir. 1. Remove and discard all ice from the bin.9. Using a clean sponge and the remainder of the 2. Switch the ice maker off.sanitizer solution, wipe the interior of theevaporator cover and the inside of the storage bin, 2. Prepare 2 gallons of an approved sanitizertaking care to wipe all surfaces that are normally in solution in accordance with the instructions on thecontact with ice. package.10. Replace the evaporator cover. Replace the 3. Using a clean sponge wipe the inside of thefront panel. storage bin and door, taking care to wipe all11. Move the master switch to ON. surfaces. 4. Rinse the interior of the storage bin using clean water and the sponge used in step 3. 5. Switch the ice machine back on. RESERVOIR DRAIN ON/OFF/WASH SWITCHOctober 1993 Page 20

FREEZING CYCLE OPERATION MCM1062RWater from the sump assembly is pumped to the Low Temperature Freeze:water distributor system at the top of eachevaporator plate. From the water distributor the When the outside air temperature is low, the Headwater cascades by gravity over all cells of the plate Pressure Regulator will close off the liquid line toand to the sump assembly below. the receiver, causing liquid refrigerant to back up into the condenser unitl the head pressure buildsAt the beginning of the freezing cycle, the electrical up to 220 PSIG. While this is occuring, the headcircuit is completed to the compressor and the pressure regulator passes discharge gas into thewater pump. The water pump operates receiver to keep the refrigerant flowing.continuously, through both the freezing cycle andthe harvest cycle.During the freezing cycle, the hot gas solenoidvalve is CLOSED and the water inlet solenoidvalve is CLOSED. When the ice cubes are partiallyformed, the cube size control will sense thetemperature at which it is preset to CLOSE. Thiswill complete the electrical circuit to the timer. Thetimer then controls the remainder of the freezingcycle. The timer will keep the icemaker operatingin the freezing cycle for a selected length of time.This will give the ice cubes time to fully form. afterthat selected length of time, the timer will switchthe icemaker into the harvest cycle, through thecontacts of the timer assembly microswitch.October 1993 Page 21

MCM1062RHARVEST CYCLE - HOT GAS BYPASSWhen the timer switches the icemaker into the Pump Down Cycle:harvest cycle, high pressure, high temperature gasrefrigerant being discharged from the compressor When the ice level control is open at the end of theis diverted from the condenser through the hot gas harvest cycle, power is removed from the liquidsolenoid valve into each evaporator plate. During line valve coil, and the pump down cycle begins.this cycle, the refrigerant bypasses the condenser. The compressor will continue to run until the pumpln the electrical circuit, both the compressor and down control, sensing low side pressure, opens atthe water pump are operating and the hot gas 20 PSIG.solenoid valve is energized and OPEN and thewater inlet solenoid valve is OPEN.The finished ice cubes are released from the sidesof each evaporator plate by the warming effect ofthe hot gas condensing in each evaporator plateand the water cascading over the ice cubes. Thereleased ice cubes drop into the ice storage binbelow. At the end of the harvest cycle, the timercam will push the actuator arm to the microswitchIN. If the ice level control is still CLOSED, a wholenew cycle will begin. If the ice level control isOPEN, the icemaker will begin to shut OFF.October 1993 Page 22

MCM1062RSERVICE DIAGNOSIS POSSIBLE CAUSE PROBABLE CORRECTION 1. No electrical power SYMPTOM 2. Circuit breaker tripped or fuse 1. Restore power No ice, machine does not run blown 3. High pressure control open. 2. Reset breaker or replace fuse, No ice, compressor does not run, check for electrical fault. rest of ice machine does. 4. Bin level control holding machine off 3. Reset HPC, check fan motor for No ice, no water over evaporators 5. High temp. cut out open proper operation, and condenser No ice, everything runs coil for dirt. Low ice production 6. Timer switch open 7. On/Off switch open 4. Check ice level control circuit. 8. Circuit board open See page 25. 1. Compressor on/off switch open 5. Hot gas valve leaks thru, replace hot gas valve 6. Replace timer 7. Check or replace switch. 8. Replace circuit board. 1. Check or replace switch 2. Open contactor coil 2. Replace contactor 3. Liquid line valve does not open 3. Check electrical connections to 4. Pump down pressure switch liquid line valve, check coil, check does not close valve operation 5. Thermostatic Expansion valve 4. Defective switch, or liquid line clogged or does not open. valve does not open, or low on 1. Water pump does not pump refrigerant; check/replace 2. No water in reservoir 1. Too much heat load 5. Check/replace TXV. 2. Low on refrigerant 1. Check/replace water pump 3. Suction pressure too high 2. Check/replace water inlet valve. 1. Too much heat load. 1. Check for slow leak thru of water 2. Compressor inefficient. inlet valve. 3. Non condensable gasses in refrigeration system. 2. Check pressures, if low find/repair leak. weigh in charge. 3. Defective compressor - replace 1. Check condenser air inlet and water temperatures. 2. Replace compressor 3. Check head pressure, if very high, and no other reason is suspected, replace refrigerant charge. October 1993 Page 23

MCM1062R POSSIBLE CAUSE PROBABLE CORRECTION 3. High head pressure, a result of a 3. Clean condenser, check fanSERVICE DIAGNOSIS dirty condenser motor 4. Hot gas valve leaks thru 4. Replace hot gas valve SYMPTOM 5. High air temp. for condenser. 5. If possible, reduce condenser air Low ice production inlet temperature. 1. Cube size control will not close 1. Check temp. of suction line, cube No ice falling in bin, unit frozen up size control will not close if temp. 2. Timer motor open too high. If temp. low enough, Ice maker stuck in harvest cycle 3. Plug in relay contacts open replace cube size control 4. Not enough time during the 2. Replace timer Ice is mal-formed harvest cycle to drop all ice 3. Replace relay 5. Cube size wrong 4. Adjust timer for more harvest time Water overflows from reservoir into 6. Hot gas valve restricted. bin. 7. Not enough water to help harvest. 5. Adjust cube size 6. Replace hot gas valve. 8. Head pressure too low 7. Check for restriction of water supply. 1. Relay coil open 8. Check pressure control valve. 2. Timer stuck in harvest cycle Check for low refrigerant charge. 1. Replace relay 3. Timer microswitch N.O. contacts 2. Check for power to timer motor, if will not close. power replace timer, if no power to 1. Shortage of water timer motor, replace relay. 3. Replace timer. 2. Evaporator water passages restricted. 1. Check for restriction of water 3. Cube size set wrong supply. Check for leak. 1. Restricted sump drain 2. Clean ice maker. 3. Adjust cube size control 1. Repair drain 2. Inlet water valve lets in too much 2. Replace valve water October 1993 Page 24

MCM1062RSERVICE DIAGNOSIS: Ice Level Control CircuitCONDITION DETERMINE CAUSE PROBABLE CORRECTIONIce Machine does not run, it has A. Listen for a ticking sound frompower to it, the high pressure transducer. If no noise, go to C. If there is acontrol is closed, the on/off switch is noise, check for a light on the boardset to ON (the compressor will not B. Open bin door and twist (models built after 4/93). If there is aoperate until the liquid line valve transducer 1/4 turn and pull out. DO light on, check relay contacts N.O.opens, but the pump should be NOT UNPLUG with power and COM. The contacts should beworking if there is no ice in the bin). connected. Examine the CLOSED. If closed, go to D. If not, transducer, the inside must be replace the board. If light is off, orMachine runs, makes ice, switches clean and dry. prior model, go to B.on and off, but ice level cannot be C. Check power to bin levelcontrolled. control board. If the inside of the transducerMachine runs, but will not shut off. (above screen) was wet, replace it. D. Disconnect electrical power Set bin level to FULL and aim at an and test ice machine circuit by object about 1-3 feet away. attaching a jumper wire between bin Machine should restart, if not go to thermostat posts on circuit board D. part no. 12-1912-01 (the circuit board with the timer on it). Should be 12 volts from Reconnect power. transformer, if not replace E. Transducer or ice level board transformer. If there is power go to assembly defective. D. Ice level switch may be defective. If machine does not start go back On boards with a light, check by to machine circuit. If machine moving switch & watching light. starts, disconnect electrical power, Board relay stuck closed. Check remove jumper wire and reconnect relay. electrical power. Then go to E. Replace transducer. Set bin level to FULL and aim at an object about 1-3 feet away. Machine should restart. If this does not repair unit, replace the board. Replace ice level switch If COM and N.O. are closed when power is off, replace board. If open, go to B above.PARTIAL VIEW OF PLUG - IN Electrical Shock Hazard CIRCUIT BOARD RELAY Can Cause Personal Injury. 12-1912-01 BIN THERMOSTAT Disconnect Power Before Servicing. TIMER POSTS Bin Thermostat Posts at Line MENTIONED Voltage. IN “D” ABOVE October 1993 Page 25

MCM1062R 5. Unplug transducer and remove from the machine.REMOVAL AND REPLACEMENT 6. Reverse steps 1-5 to reassemble.TRANSDUCER1. Disconnect electrical power BEFORE removingtransducer.2. Open bin door and locate the transducer socket.3. Twist inner portion of transducer counter-clockwise and push up gently.4. Pull transponder down until plug connection isaccessible.TRANSDUCER LOCATION TRANSDUCER SOCKETTRANSDUCER PLUG CONNECTION REMOVAL OF TRANSDUCER October 1993 Page 26

REMOVAL AND REPLACEMENT MCM1062R/////////////////////////////////WARNING////////////////////////////// Cube Size Control To remove the cube size control:Disconnect electrical power before beginning. 1. Remove front panel. 2. Remove cover from control box.///////////////////////////////////////////////////////////////////////////////// 3. Trace capillary tube, from the cube size control to the refrigerant suction line.Water Distributor Tubes And Manifold Tubes 4. Remove the coiled capillary tube bulb from the tube well on the suction line.To remove the water distributor tube and manifold 5. Remove electrical leads from the cube sizetube: control. 6. Remove screws and the cube size control. To1. Pull out to unsnap catches and remove the front replace the cube size control, reverse the removalpanel. procedure. Be certain that the bulb is re-insulated.2. Remove the evaporator cover. WATER DISTRIBUTOR3. Slide the water distributor tube to the front about1/8-inch along the top of the evaporator plate, until TUBESthe water distributor tube can be unsnapped fromthe flexible notch and lifted upward to the rightside.4. Unsnap and disconnect water distributor tubesfrom the water manifold section. To replace thewater distributor tubes and manifold tubes, reversethe removal procedure. BE SURE the notches inthe water manifold tubes properly engage thealignment keys in the tee. BE SURE the waterdistributor tube is securely fastenedat the notch at both sides of theevaporator plate. Check identicalattachment for the left waterdistributor tube and notch; also, thatthe distributor/manifold connectionsat the top center of each evaporatorplate is snug against the top of theplate.CUBE SIZE INLET WATERCONTROL VALVE October 1993 Page 27

MCM1062R Inlet Water Solenoid Valve AssemblyREMOVAL AND REPLACEMENT To remove the inlet water solenoid valve assembly://////////////////////////////WARNING////////////////////////////////// 1. Shut OFF water supply to machine.Disconnect electrical power before beginning.////////////////////////////////////////////////////////////////////////////////// 2. Loosen and remove outlet water line from theWater Pump inlet water solenoid valve assembly.1. Remove front panel.2. Remove evaporator cover. 3. Remove screws and pull the water solenoid3. Unplug water pump electrical connection. valve out to gain access. ELECTRICAL ELECTRICAL INLET WATER CONNECTION CORD SOLENOIDWATER DISCHARGE OUTLET PUMP HOSE TUBE REMOVAL OF THE WATER PUMP REMOVAL OF INLET WATER SOLENOID VALVE 4. Pull electrical cord from solenoid coil terminals.4. Remove thumb screw retaining pump to cross 5. Remove inlet water fitting from the waterbrace. solenoid valve. To replace the inlet water valve assembly, reverse the removal procedures.5. Pull pump partially out of reservoir and removedischarge hose.6. Remove two nuts holding pump cover to pumpbody; separate the two and remove the pump fromthe icemaker.7. Reverse to reassemble.8. Replace all panels.9. Reconnect electrical power. October 1993 Page 28

REMOVAL AND REPLACEMENT MCM1062RHead Pressure Control Valve Thermostatic Expansion Valve 1. Remove the side service panel, and top panel if1. Remove side service panel, and top panel if possible..possible. 2. Discharge and recover the refrigerant from the system. Reclaim it if possible.2. Discharge and recover refrigerant from the 3. Locate the TXV sensing bulb on the suction line,system. unwrap the insulation and remove the bulb from the clamp.3. Break off the process tube on the dome of the 4. Cut out or unsweat the old TXV from the tubinghead pressure control valve. connections. 5. Wrap the new TXV body in wet cloths or other4. Cut out or unsweat the tubing connections to efficient heat sink material.the valve. Remove the valve. 6. Re-attach the TXV bulb to the suction line in the same place as the original. Be certain to5. Wrap the new valve in wet cloths or other re-insulate the bulb.effective heat sink material, and sweat the tubing 7. Sweat in the new valve. Do not overheat.connections to the valve. 8. Weigh the nameplate charge into the receiver. 9. Replace all panels removed for service.6. Weigh the nameplate charge into the receiver. 10. Reconnect electrical power.7. Replace all panels.8. Reconnect electrical power.Hot Gas Valve or Liquid Line Valve1. Remove the side service panel, and top panel ifpossible.2. Discharge and recover the refrigerant from thesystem.3. Remove the electrical connections from the coilof the valve4. Cut out or unsweat the valve at the tubingconnections, remove the valve from the icemaker.5. Install the new valve, wrap it in wet cloths orother efficient heat sink material.6. Sweat the tubing connections to the valve.7. Connect the electrical wires to the terminals ofthe valve coil.8. Weigh the nameplate charge into the receiver.9. Replace all panels removed for service.10. Reconnect electrical power.October 1993 Page 29

Like this book? You can publish your book online for free in a few minutes!
Create your own flipbook